This invention relates to a sewing machine which is capable of warning an operator, what and where an accidentally happened trouble is, by means of sound or voice.
Employment of a warning lamp for alarming an occurrence of a trouble or abnormal condition in a sewing machine to an operator has been traditionally well known. There can be various types of troubles to take place in sewing machines, such as breakage of an upper thread, overload of a drive motor, etc. In the conventional system, an occurrence of any one kind of trouble causes a warning lamp to be lit for visually alarming the operator. Mere lighting of the warning lamp is not enough to let the operator know specifically where and what kind of abnormal condition is taking place, and requires of the operator too much time for making proper repairs.
For solving this problem a sewing machine was provided, wherein an operator could be informed of the abnormal condition taking place therein by means of a sound or voice, which was disclosed by the present applicant in the specification of the patent application U.S. Ser. No. 264,613. Some problems are however still left unsolved even in that invention. If the operator of that sewing machine forgets the once heard alarm sound or continues a new operation without making proper repair, the machine may be damaged and even the operator may be injured.